The purpose of this invention is to provide a snap lock assembly which can be quickly mounted on a shaft without passing over an end of the shaft and a tool for applying said assembly.
In conventional nut and bolt assemblies, the nut is passed over the free end of the bolt and threaded into position to secure a member between the head of the bolt and the nut. This, of course, requires access to the free end of the bolt, and it may also require the expenditure of a substantial amount of time to thread the nut into position.
In the past others have sought ways to expedite the assembly of nuts onto threaded members. In the assembly disclosed in U.S. Pat. No. 1,406,804, issued Feb. 14, 1922, to W. S. Alexander and entitled "Quick Releasable Nut and Bolt," an internally threaded nut is split into two segments which may be placed in mating relationship with external threads on a bolt at any point intermediate the length of the bolt. The nut segments are held in position by means of a unitary retaining member which has wedge-shaped surfaces which engage and interact with wedge surfaces on the nut segments so that, when the bolt is tightened, the retaining member is forced into surrounding engagement with the nut segment to maintain the nut in place. In that device, however, the mating member is unitary and must be slid over the free end of the bolt. Therefore, the assembly is not usable with a threaded member when there is no accessible free end.
A significant advance was realized in the art by the disclosure of the above-identified U.S. Pat. No. 4,274,323. In this connection several embodiments are disclosed of an assembly which may be facilely mounted about a shaft without requiring access to the ends of the shaft. Most of the embodiments disclosed in U.S. Pat. No. 4,274,323, however, comprise four components. Accordingly, such shaft-mounted assemblies may be somewhat complicated to manufacture and assemble for certain purposes. Further, although some embodiments are composed of only two segments, such assemblies are not positively retained in an assembled condition, which can be a disadvantage in some applications.
The difficulties suggested in the preceding with regard to prior shaft-mounted assemblies are not intended to be exhaustive, but rather are among many which may tend to limit the effectiveness and satisfaction with prior units. Other noteworthy problems may also exist; however, those presented above should be sufficient to demonstrate that prior lateral shaft-mounted assemblies will admit to worthwhile improvement.